Transcript for Protecting Malls in the United States Against Terror Attacks

But nearly every major mall does have a plan. Abc's justice correspondent pierre thomas shows us how police are already training for every possibility. Reporter: Active shooters, terrorists in a mall. The nightmare scenario for local police. In this training exercise in newport news, virginia, police respond to a shooter where 200 volunteers play the role of scared shoppers. The dead and the wounded. As you see here, police don't wait. They quickly go in, locate and confront the shooter. Across the country, the police training for attacks on soft targets, malls, hotels, schools. Run to the gunfire, engage. Concerns here at home have been mounted since the devastating 2008 attack in mumbai, india, where terrorists overran hotels and shopping centers. Captain robert ballistic is s.W.A.T. Team commander for montgomery police in maryland. He says now even patrolmen will come to malls under attack ready for heavy-duty fighting. We have several hundred officers on our department that have been trained in an m4 assault type rifle. Semiautomatic. Reporter: You go in hot and heavy. Yes, we are. We know the terrorists are bringing this type of weaponry to the scene. Reporter: If terrorists come they're coming to kill people. We recommend you flee immediately if you know they're coming up to you have to probably most likely either run to an another location or hide if that's your best avenue and lastly, if it gets to the point where these individuals are beginning to engage and are coming into your room you do need to fight. Reporter: The kenyan scenario has yet to play out on the home front but police say they have to prepare as if it will. Pierre thomas, abc news, washington.

This transcript has been automatically generated and may not be 100% accurate.

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